Hammond 164E28 2.4VA 28V Center-Tapped PCB Transformer, 115V Primary

The 164E28 is a 2.4VA low-voltage power transformer designed to mount directly on a printed circuit board. It has a single 115V primary rated for 50/60 Hz operation and a low-profile, split bobbin construction, making it a fit for OEM engineers and board designers who need a 28V centre-tapped secondary in a compact footprint. The output is 28V C.T. at 0.085A with the windings in series, or 14V at 0.17A in parallel.

Construction uses dual secondary windings, non-concentrically wound, which gives low primary-to-secondary coupling without the need for an electrostatic shield. The insulation system is Class B, rated 130 degrees C, with a 2,500V RMS hipot. All windings are intended to be used together in either the series or the parallel connection.

The E-size body measures 1.38 in long by 1.13 in wide by 1.19 in high and weighs 0.25 lb per the series specification sheet. At 2.4VA it needs no mounting hardware: the unit is held by its P.C. board pins, which use industry-standard pin spacing.

The 164E28 drawing labels each secondary winding (pins 5-6 and pins 7-8) at 14V, 86mA, with the 115V primary on pins 1 and 4; pin numbers are embossed on the bobbin flange.

The transformer is c UL us recognized and listed as RoHS and REACH compliant. Where a design must run from 115V or 230V, the dual-primary equivalent in the same series is 162E28.